How To Make Ear Savers Using Mold Star™ 20T Smooth‑Cast™ 65D


Wearing a mask for any amount of time can be painful on the ears. In this DIY tutorial video, Milo shows how to create resin ear savers using a Mold Star™ 20T silicone mold and Smooth-Cast™ 65D casting resin.

The 3D print file for these ear savers can be found at:

Project Goals:

  • Provide long term relief to your ears when wearing masks
  • Resin needs to be durable and semi-rigid
  • Create multiple castings quickly and easily

For this project, a master pattern was 3D printed.  Mold Star™ 20T silicone is mixed and poured over the pattern to create a flexible mold.  Smooth-Cast™ 65D semi rigid resin is then mixed and poured into the mold cavities to create multiple ear savers.

Mold Star™ 20T is an easy to use Shore 20A translucent platinum silicone that is mixed 1A:1B by volume (no weighing scale necessary). It features a relatively low viscosity and vacuum degassing is not required for most applications. Pot life is 6 minutes and cure time is 30 minutes at room temperature.

Smooth-Cast™ 65D semi-rigid urethane casting resin cures quickly to a semi-rigid plastic that offers excellent impact resistance. This plastic is easy-to-use (mix ratio is 1A:1B by volume) and has low viscosities for minimal bubble entrapment. Vibrant colors are possible by adding SO-Strong™, UVO™ or Ignite™ color pigments.

Materials Used in this Tutorial

  • 3D Printed Master Pattern
  • Sculptex™ Soft Clay
  • Ease Release™ 200
  • Mold Star™ 20T Silicone
  • Mixing Cups and Sticks
  • Smooth-Cast 65D Urethane Resin